I thought I might start with a relatively simple and already fairly popular family, Dynastes, also called "Hercules," "rhinoceros" or even "unicorn" beetles. This group includes some of the longest and strongest of all Coleoptera, thanks to the unique horns of the adult males. A single long horn curves out from the head and another from the insect's thorax, forming a remarkable crab-like claw with the animal's entire head as the lower joint. This weird arrangement is used primarily to grab and flip other males, who compete with one another for a limited number of females. What other animal uses its forehead and its back as tongs? Breeding these insects for tournament fighting is a major hobby in some countries, particularly Japan, and was a partial inspiration for the Pokemon franchise.

#19 - Psephenidae - the "Water Penny" Beetles

Adults of this unusual family are fairly mundane-looking little beetles, but lay their eggs in water where they hatch into a completely unique type of larvae. With an armored back that flares out into a flattened sucker, these tiny "water pennies" cling limpet-like to smooth rocks under powerful currents, even waterfalls and white-water rapids where other creatures (including potential enemies) would be dashed to pieces. Their legs are specially adapted for scraping algae or other detritus into their tiny mouths, and they may even prey upon other small enough organisms in their wake.

Often distinguished by a long anteater-like snout, the Curculionoidea or "weevils" are actually the largest beetle subgroup of all and one of the most common "superfamilies" in the animal kingdom. Though most of them are already fairly comical looking as far as beetles go, the two known species in the genus Trachelophorus are even sillier. The male alone possesses a greatly elongated head and thorax forming a stiff, awkward "arm" with a single joint, which he uses during courtship and nest building; by tightly rolling a leaf around his head, he creates a protective tube in which the female will lay a single egg. The longer his neck, the more attractive he is to the females.

Do weevils suffer neck envy?

#17 - Rhipiceridae - the Cicada Parasite Beetles

When young cicadas (another type of bug, not a beetle) hatch, they begin a long journey from the upper branches of their tree to deep beneath the ground, where they attach to subterranean roots and will feed in place for many years - sometimes up to seventeen - before they emerge en masse to molt into winged adults, mate, lay eggs and die over the course of a few months. It is during this time that Rhipicerid beetles begin their own brief mating frenzy:

These incredibly tiny, snoutless members of the Weevil family are a rare example of a fully social beetle and one half of a sophisticated symbiotic partnership. The adult beetles typically excavate tunnels or "galleries" in dead or dying wood, not to feed upon the wood directly, but to cultivate wood-digesting ambrosia fungus, which constitutes their entire diet and extracts all the nutrients they need from the surrounding tree. Both beetle and fungus are entirely dependent upon one another for existence, with special pouches on the insect's body adapted to collect and transport fungal spores to new trees.

One species of ambrosia beetle, Austroplatypus incompertus, is the very first beetle to ever be recognized as eusocial, meaning that it forms colonies of specialized castes like those of ants, bees and termites, including both reproductive and non-reproductive roles.

#13 - Platypsyllus - Beaver Beetles

Eyeless, wingless and smaller than a pinhead, these beetles closely resemble fleas because they, too, live in the fur of mammals - specifically beavers. Unlike fleas, however, these "beaver bugs" are harmless and perhaps even hygenic to their hosts, feeding only upon dead flakes of skin, mites and other contaminants in beaver fur. Few other beetles are so heavily adapted to the body of another animal, and thus far, these seldom-seen weirdos have been found living on virtually no other type of mammal.

#12 - Gyrinidae - the Whirligig Beetles

Many beetles are known for their amphibious habits, but the Gyrinidae are adapted unlike any other insect to a life half-submerged at the water's surface, suspended perfectly by surface tension where they buzz about like miniature motorboats. A whirligig beetle's four paddle-like rear legs beat up to sixty times a second to propel it at high speeds, while the foremost pair of limbs are adapted into a set of gripping claws, used to prey upon insects that fall into the water. Highly unusual are the beetle's eyes; a single huge pair run all the way through the head to protrude out both the top and bottom, giving the appearance of four separate eyes while giving the insect an equally detailed view of the sky above and water below.

The order Coleoptera (sheath-winged) or "beetles" are not only the largest order of the class Insecta, but the largest order of animal life by a staggering margin. Nearly half of all known insects are some variety of beetle, constituting roughly a quarter of all life as we know it - and hundreds of new beetles are discovered every year. To put this in perspective, there are more named species of weevil alone than every fish, amphibian, reptile, bird and mammal on our planet put together, and weevils are just one of the many families and superfamilies comprising the Coleoptera. So what exactly defines a beetle?

Though we're about to talk about some pretty deviant forms, most beetles are simple to identify by the presence of elytra. Actually a pair of hardened wings, the elytra form a tight shell against the beetle's abdomen and can usually flip open to unfurl the rear set of flight wings. While this setup makes their flight fairly awkward, it also offers excellent protection from predators and has no doubt contributed to the Coleoptera's success.

Beetles are also among the insect groups to always undergo "complete metamorphosis," meaning that they hatch from eggs as worm-like larvae or "grubs" and pass through a normally immobile pupal stage before becoming adults. As with many insects, the larval stage often represents the majority of the animal's lifespan, while the "adult" is little more than a short-lived reproductive stage. Now, I'm sure your next question is undoubtedly "are beetles bugs?" which is a slightly less stupid question than many of you probably think.

Here, we see a predatory stink bug impale prey on its straw-like feeding tube. Bugs are not beetles, but members of the order Hemiptera, the second largest group of insects. Though they look superficially similar to beetles at first glance, bugs are only distantly related and do not pass through a larval stage, never possess elytra (notice the flat wings simply folded over one another) and always possess a fused, straw-like sucking mouth. Beetles never possess this type of mouth, but usually chew their food with mandibles, the more popular of the insect mouth-parts.

Of course, nature likes to throw curveballs now and then, so there are some beetles that look more like ants or wasps than beetles or bugs. Many beetles are flightless, and may not have elytra or wings at all. Some beetles don't even leave the larval stage. Whether you're a life-long entomologist or barely know your silverfish from your firebrats, I hope you'll find something interesting in my stupid little countdown list of the weirdest, coolest, prettiest and most extreme Coleoptera on Earth...

Employing their beautiful feelers to sinister ends, these beetles sniff out trees laden with Cicada eggs and lay their own eggs in vast numbers, which hatch some time after the new generation of cicadas. The almost invisibly tiny beetle larvae drop to the ground and wind their way through soil, hunting for cicada nymphs to attach to. The immature beetles will live their lives as a parasite's parasite, growing large, fat and sedentary off the blood of a nymph that in turns feeds from the same tree root for most of its life.

#15 - Scarabaeinae - the Dung Beetles

Revered in ancient Egypt, the Scarabaeinae are famous for their habit of rolling animal droppings into spheres. This is primarily performed by the male, whose dung-ball is both an advertisement of his manhood and a future nursery for his offspring. The female may assist in rolling the ball far away from competitors or simply ride along while her mate does all the work. Picking out a prime spot, they load up the dung-ball with eggs and sometimes bury themselves with it to watch over the larvae.

As competition for Mother Nature's special brownies can naturally get pretty fierce, some species don't even wait for it to hit the ground; they'll happily camp out for hours to get pieces of crap straight from the source, much like otaku.

Another, possibly weirder dung beetle is Zonocopris gibbicollis, which lives only on the bodies of giant African snails to feed on the host's feces. Please thank - and visit! - Kabinet of Curiosities for drawing my attention to this.

Yes, some species just cling tenaciously to the buttocks of large mammals such as this titi monkey, waiting for the next steamy bus ride to the forest floor. When their host begins defecating, the beetles simply hop aboard the droppings and hang on for dear life, guaranteeing themselves first dibs on one of insectkind's hottest commodities.

Gyrinidae have a natural drive to gather in large numbers that appear at first glance to exist in total chaos, with dozens of individuals zipping and whirling about one another at incredibly high speeds. Like cells in a brain, the insects are actually communicating non-stop to maintain perfect order, with a specific placement in the group for each individual.

Combined together, the volatile ingredients reach nearly boiling temperatures and build pressure until they "flash evaporate," exploding from a specialized opening near the anus in a burst of searing hot, vile smelling and vile tasting vapor. The entire process - from frightened beetle to killer gas attack - is so instantaneous that it can repeat several hundred times in a fraction of a second, appearing as a single blast to the human eye, and its highly flexible abdomen allows it to aim the explosion in almost any direction.

These carabids don't look that unusual or dangerous on the outside, but that mistake has probably left mental scars on millions of insect-eaters. Housed within the abdomen of a brachinus beetle are two separate chemical compounds; hydrogen peroxide and hydroquinone. When it feels threatened enough, the insect empties the two chemicals into a "mixing chamber" of water and special catalytic enzymes...

The closely related "stag" beetles (Lucanidae) are similar to the Dynastes, but males spar using mandibles so huge that they are useless for eating. Both groups spend many years as grubs in soil or rotting wood, living for only a few months as adults. HERE you can watch the amazing (and ultimately ridiculous) adventure of one stag beetle (a Darwin's beetle) fight his way to romance and forget when to stop.

The "rove beetles" or Staphylinids are the second largest beetle family after the weevils, though they scarcely resemble beetles at all. Their wings, when they have wings, are folded under extremely short elytra leaving most of their tapering, flexible bodies uncovered. Most of them are extremely tiny, carnivorous and adapted to highly specific diets. The Stenus genus prey upon extremely tiny arthropods such as mites or springtails, and have adapted an unusual means of capturing their meals. Their labium (often described as an insect's "lower lip") can be "launched" by blood pressure on a long, thin stem like the tongue of a chameleon, tipped with various barbs and even an adhesive secretion to reel in helpless creatures.